Ore-concentrator.



No. 695,064. Patented Man-1|, |9o2'.

Y 1.. LO0K.

ORE CONCENTBATDR.

' (Application filed Aug. 14, 1900.; (No Model.) 7 SheetsSheet I.

I0, 695,064. Patented Man. II, I902;

L. LOOK.

DRE GONGENTBATOR.

(Application flled Aug. 14, 1900.)

Z Sheets-Sheet 2.

(Ilo Model.)

V L. LOOK. DRE CONCENTRATOR. (Application filed Aug. 14, 1900.)

Patented Mar, II, 1902.

7 sh eets shaet 3.

(No Model.)

. .QMSIJQ No. 695,064. 1 Patented Mar. ll, I902.

L. LOOK.

ORE CONOENTBATOR.

(Application filed Aug. 14, 1900.) (No Model.) 7 Sheets-Sheet 4.

Patented Mar. l| I902. L. LOOK. ORE CONCENTBATOIL.

(Application filed Aug. 14. 1900.)

7 Sheets-Sheet 5.

(NoModaL) 0., wAsuium-om a. c.

No. 695,064. Pat ented Mar. :1, 1902..

L. LOOK.

ORE CONCENTRATUR.

(Application filed. Aug. 14', 1900.) (No Model.) 7 Sheets-Sheet 6.

@' fmwki" No. 695,064. Patented Mar. H, l902.

. L. LOOK.

DREGONOEN TBATDR.

(Application filed Aug. 14. 1,900.]

7 Sheets-Sheef 7.

- No Model.)

IZjJl ZZ Wkmssu nrrnn drn'rns Pnrnivr amen.

LUTHER LOOK, OF LOS ANGELES, CALIFORNIA, ASSIGNOR TO THE NElV STANDARD OONOENTRATOR CO., OF LOS ANGELES, CALIFORNIA, A

CORPORATION OF CALIFORNIA.

ORE CONCENTRATOR.

SPECIFICATION forming part of Letters Patent No. 695,064, dated March 11, 1902. Application filed August 14, 1900. Serial No. 26,887. (No model.)

To aZZ whom it may concern:

Be it known that I, LUTHER LOOK, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Ore-Concentrators, of which the following is a specification.

My invention relates to improvements upon my inventions in ore-concentrators set forth in Letters Patent'of the United States No.

439,962, patented November 4, 1890, and No.

526,242, patented September 18, 1894. In the later one of said patents I have shown a table of the Rittinger type-t hat is to say, a swinging percussion-table. In each of said patents the surface or lighter portion of the pulp is acted upon by clear water, which has a tendency to carry the lighter portion downward and backward, while the mineral is impelled across the table underneath the surface of the lighter material and in a direction at an angle thereto, which angle varies, depending upon the adjustment and upon the various forces at work.

This invention relates to the construction and mechanism of the machine.

The object of my present invention is to increase the efficiency and capacity of this class of machines. It is applicable for use with various kinds of concentrating-tables.

Other objects are economy of water and power, simplicity and ease of operation and adjustment for different ores, and simplicity and lightness of construction, combined with greater capacity.

The principal feature of this invention is that the swinging table is held by springs intermediate the ends of the throw or path of the table, and the cam which moves the table in one direction acts to move the table during a greater portion of the rotation of the cam, but is freed from acting upon the table at the instant of the percussion. An object of the invention is to give to the table-a perfectly smooth movement under a high speed of vibration. I employ a cushioning-spring and a stationary stop for arresting the motion of the table when it has been swung to the percussion side oi the machine. The purpose of the spring is to check and cushion the movement of the table immediately before the table reaches the stationary stop. In my invention I balance the table by means of springs, so that the table rests normally on a balance under the force of two springs acting in opposite directions. The table when thus balanced has a natural rate of vibration and will vibrate a certain number of times per minute depending upon the tension of the springs, in a manner similar to the balancewheel of a watch. The number of complete vibrations per minute must be greater than the number of revolutions per minute of the cam which operates the table, so that the cam will at no time outrun the table and overtake the table-Operating mechanism. The tension of the springs governs the number of vibrations of the table per minute for a given weight of table, and to increase the number of vibrations per minute the tension of the springs must be increased. In my invention I provide means for adjusting the tension of all the springs, so that the rate of vibration can be adjusted to the number of bumps per minute produced by the cam. I preferably use a cam of special form for varying the speed at different portions of the stroke as required for the most efficient separation of the mineral from the waste and to prevent any bumping on the cam. It is an object of my invention to do away with any movement of the table which is liable to cause internal vibration in the pulp while passing over the table, and which would thus prevent the finer mineral from settling to the table. In practical operation there are certain limits of length and frequency of stroke within which the most ef fective action can be obtained; and a purpose in view of my invention is to secure a sufficient length and rapidity of stroke to keep the pulp lively and allow the mineral to settle to the table and to cause it to be thrown toward the upper side of the table While lying on the table, and to do this without producing any eddies, cross-currents, or vibrations in the pulp, which would keep the finer mineral in suspension. I purpose to give to the table such a movement as will tend to throw the mineral across the table and diagonally upward against the course of the water. The

surface of the table may be rifiled or unriffied, the purpose of the riffies, as is well known, being to retard the flow of the pulp at the bottom to give the mineral a better chance to settle.

- Various forms of riflie-tables have been invented by me for use with the mechanism herein set forth, and the same forms the subject-matter of a separate application for patentpending in the Patent Office contemporaneous with this application, Serial No.22,688, filed August 14, 1900, and patented July 16, 1901, No. 678,793. I have therefore shown in the accompanying drawings a plain table of a shape whichI at present deem best adapted to the mechanism described and claimed in this application.

The accompanying drawings illustrate my invention.

Figure I is a perspective view of an ore-concentrator constructedin accordance with this invention. Fig. II is a perspective view of the same, excepting that the table has been removed in order to more clearly show the operative parts in the positions they are in when the table is in place and at rest. Fig. III is a plan of the machine. Fig. III is a fragmental plan section on line III III, Fig VI. Fig. III is a diminutive sectional view of the frame and table on line III III", Fig. III. Fig. IV is a fragmental elevation of the cushioning, tempering, and balancingspring. Fig. V is an elevation of the machine looking at the discharge end. Fig.VIis an elevation of the machine looking at the feed end. In this view the feed-box and pulp-supply pipe are omitted. Fig. VII is an elevation of the power side of the machine. Fig. VIII is an elevation of the percussion side of the machine. Fig. IX is a fragmental detail to illustrate the flexible connection or link-support for the yoke at the feed end of the table. Fig. X is a fragmental detail of the intermittent means for moving the table in one direction and the spring for returning the table in the other direction to produce the percussion. Fig. XI is an enlarged detail of the intermittent means for moving the table away from the percussion side. Fig. XII is a sectional elevation on line XII XII, Fig. XI, looking to the left. Fig. XIII is a plan section on line XIII XIII, Fig. XI. Fig. XIV is a sectional elevation on line XIV XIV, Figs. XVI and XVII, looking toward the feed end of the concentrator. Fig. XV is a like section on said line looking toward the discharge end of the concentrator. Fig. XVI is a sectional elevation on line XVI XVII, Figs. XIV and XV, looking toward the percussion side of the table. Fig. XVII is a like sectional elevation looking toward the power side of the table.

The frame of the machine is composed of two sills 1 2, which extend in the direction in which the table swings. 3, 4., 5, and 6 indicate upright posts fastened to said sills.

7 and 8 indicate plates on top of the posts and extending parallel with the sills 1 and 2,

respectively.

9, l0, and 11 indicate stringers which connect the sills 1 and 2.

12, 13, and 14 indicate top stringers which connect the plates 7 and 8 and extend paral lel with the bottom stringers 9, 10, and 11.

The posts 5 and 6 are the bumping-posts and are provided with bumping-plates 15 and 16, respectively. One of these plates 15 is wedge shape and is adjustable upon a slanting face 17 of the bumping-post 5, the purpose of this being to adjust the percussion-faces exactly, so that when the table is thrown it will simultaneously engage both percussion-plates.

18 indicates an upright fastened to the stringers 11 and 14.- at the percussion side of the frame to form a support for the adjustable table-returning or bumping spring 19.

20 indicates an upright fastened to the stringers 9 and 12 to support the bearings of the cam-shaft 21, which preferably extends from end to end of the frame and is provided at each end, respectively,with light fly-wheels 22 and 23. 24: indicates the pulley for driving the shaft. 25 indicates the cam mounted on said shaft for moving the table in one direction.

a indicates the concentrating-table.

Z) indicates a yoke.

0 indicates flexible means at the middle of the yoke, connected with the frame for supporting the yoke.

dand eindicate links at the ends of the yoke, respectively connected with the opposite sides of the table at one end thereof.

f 9 indicate the table-supporting links at the other end of the table, the same being rerespectively connected with the table at the opposite sides thereof and connected with the plate.7 by which they are supported.

The intermittent means for moving the table a in one direction consists in the cam 25, a bell-crank lever 26, mounted on a shaft 27 and held suspended by a spring 28 and furnished with a shoe 29 on one arm-of the lever,

in position free from the cam during a portion of its stroke, but in the path of the cam throughout the greater portion of the rota tion of the cam, and a draw-rod 30, which is flexibly and pivotally connected at one end with the other arm of the lever 26 and connected at the other end with the table, so that when the cam. rotates it will intermittently throw the bell-crank lever topull the table away from the percussion side of the machine. The spring 19 is fastened to the under side of the table in direct line with the rod 30, so that the pull of said rod under the action of the bell-crank lever when operated by the cam will be in direct line with the pull of the spring 19, so that when the lever 26 is released by the cam the spring 19 will throw the table forcibly toward the percussion side of the frame to eventually strike upon the bumping-plates 15 and 16.

31indicates the percussion cushioning and tempering spring. This spring is adjustably secured to the stringers 11 14, being held by brackets 32 33, which are fastened to the stringers ll 14, respectively.

34 indicates a bolt which fastens the cushioning-spring to the bracket 32, and 35 indicates an adjustingscrew screwed through the bracket 33 to engage the lower end of the percussion cushioning and tempering spring 31 to adjust said spring 31 toward and from the table a.

36 indicates a set-nut to hold the screw 35 in the adjusted position.

The percussion cushioning and tempering spring 31 is preferably made of wood in order to avoid destruction by crystallization, which is liable to occur with springs of steel, and oxidation, which is liable to occur with rubber.

It indicates the cushioning-spring bumper, which is in the form of a bracket or angleiron fastened to thetable to engage the cushioning-spring 31, and havinga spring-engaging face which is at right angles to the direction of the movement of the table.

5 indicates a hinging-hook by means of which the spring 19 is hinged to a timberj,

which forms a part of the table a underneath the working surfaces of the table.

7t indicates a hinge-eye fastened to a timber m beneath the working surface of the table. The rod 30 is hinged to the hinge-eye 7; by a pin it.

37 indicates an adjusting-rod for the spring 19.

38 indicates the hand-nut, screwed onto the rod 37 and bearing against the bracket 39 on the upright 18. By adjusting the nut 38 the power of the bumping-spring 19 can be increased or decreased as required to produce the proper force of bump.

0 and 19 indicate the bumping-beams, fastened to the table and extending across the same underneath the working surface. These bumping-beams bump against the bumpingfaces 15 and 16, respectively.

q 1' indicate adjusting-nuts on the rods, which supports the tension-spring 28. The tension-spring 28 acts through the lever 26, connecting-rod 30, and the table a in oppo sition to the force applied to the table by the spring 19. When properly adjusted, the force of springs 19 will be considerably in excess of that of the tension-spring 28. In a machine in which the table weighs approximately five hundred pounds I find that the springs 19 and 28 should be adjusted to cause the spring 19 to hold the table when at rest and free from the action of the cam against the percussion cushioning and tempering spring 31 with a force of from two hundred to three hundred and fifty pounds. The percussion cushioning anditempering spring 31 will be of sufficient strength and of a sufficient tension to normallyhold the bumping-beams 0 13 about three-eighths of an inch away from the bumping-faces 15 16 in a machine, in which the throw of the table is seven-eighths of an inch. Under this adjustment when the machine is not in operation the shoe 29 will stand free from the cam at one position of the cam with a maximum space between the shoe and the cam of about three-fourths of an inch, and in this position the table will be about five-eighths of an inch from the extreme position in which it is to be thrown by the cam away from the bu mping-faces 15 16. The arms 'of the lever 26 are so proportioned that at the extreme throw of the cam the bumpingbeams will be drawn away from the bumping-faces from three-fourths of an inch to one inch, depending upon the character of ore to be treated. The machine is adapted for an adjustment of length of throw from a very small fraction of an inch to an inch or more; but in practice the length of throw most effective for the work is from three-fourths of an inch to an inch.

I will now describe the means for adjusting the length of throw. (See Sheet 5, and particularly Fig. XI, in which is shown the means for moving the table in one direction and the cam for actuating such means.)

40 indicates a roller pin which extends through the end of the lowerarm of the camlever 26, said lower arm being forked at its lower end, as clearly shown in Fig. XII. The

connecting-rod 30 passes through ahole 41 in pin 40.

42 indicates a washer on the connectin -rod 30 and resting against the pin 40.

43 indicates a throw-adjusting and camcushioning spring which rests against the A washer 4 2, which washer is free to move along the connecting-rod 30 to compress the spring 43 against the set-nuts 45 46 under the action of the cam, so that the power is communicated from the cam to the table gradually through the spring 43, thus relieving any jar or percussion due to the rapid rotation of the cam.

The shoe 29 is normally held by the spring 28 as far away from the cam 25 as the positionof the throw-adjusting and cam-cushioning spring 43 on the connecting-rod 30 will allow. By adjusting the spring 43 away from the cam the shoe 29 will be brought more and more into the path of the cam, thus increasing the length of the throw of the table. adjusting the spring 43 toward thecam the tension-spring 28 will be allowed to hold the shoe 29 farther away from the axis of the cam, thus reducing the throw of the table.

t indicates a hand-nut for raising and lowering the screw to, which supports the yoke b. By turning the hand-nut t the feed end r of the table will be raised or lowered.

w 00 indicate hand-nutsfor adjusting the screws y a, which support the links fg at the discharge end 47 of the table.

With a table of practical working size which I have made the length from the feed end '0 to the discharge end' is ten feet, and the greatest width from the upper side a to the lower side a of the table is about ten and one-half feet, and with a table of these dimensions the feed end may be from threeto five inches (more or less) higher than the discharge end. When a riffled table is used, a greater fall can be given than without riffles. With a riiiied table I have given a fall of five inches successfully. Without riffies three or four inches fall may be given. The table is to be adjusted slanting from the percussion side toward the power side, and the difference between the levels of the percus sion and power side at the line of the lower bumping-beam 19 may be from one-half an inch to one and a half inches.

It is to be understood that I do not limit myself to the adjustments above stated, but that I have in the practical use of my ma chine found said adjustments to be satisfactory for work upon the ores which I have treated.

. 48 and 49 indicate two parallel bars which are pivoted to the under side of the table at the discharge end of the table, preferably at the line of the lower bumping-beam 19. These parallel bars or braces extend from said bu mping-beam toward the feed end 11 of the table and are fastened to a suitable supportviz., the frame of the machine at the line of the upper bumping-beam 0. The purpose ofthese bars is to form a-brace or stay to prevent any endwise movement of the table. The parallel bars 48 49 are preferably not at right angles to the bumping-beams 0 19, being farther from the power side at the lower beam p than at the upper beamo. This arrangement produces a slight curvature of the path of the table away from the discharge end of the table, thus tending to throw the mineral diagonally across and slightly away from the discharge end of the table against the course of the clear water which is fed onto the table from the clear-water pipe 53.

50indicates the pulp-feeding pipe. 51 indicates the feed-box into which said pipe discharges. -One side of thefeed-box is provided with openings 52, through which the pulp is fed onto the feed end '0 of the table.

53 indicates the clear-water pipe which extends along the upper side a of the table. The wall 54 of the upper side of the table extends in a line slanting across the path of the table away from the power side of the table toward the discharge end and from the feed end. The preferred angle of the upper side wall 54 of the table to the path of the table is forty-five degrees. The reason for giving this angle to the upper side wall 54 of I the table is that the bumping action tends to throw the mineral toward the percussion side of the table along the path of the table-that is to say, along line of the bump. At the same time the tendency of the slope of the table is to cause the pulp to flow by gravity diagonally across said path or line of the bump downward toward the power side a and the discharge end 47 of the table. It is desirable that the mineral which remains upon the table shall have as short a distance as possible to travel before it reaches the upper side a of the table, where it will be acted upon by the clear water, and that it shall have as long a distance as possible to travel while under the action of the clear water. The resolution of the forces at work in the table makes an angle of forty-five degrees to the line of bump or path of the table, the most desirable at which to feed the clear water to the upper side ct of the table. The clear-water pipe 53 extends parallel with the upper side wall 54 of the table.

55 indicates the trough into which the coucentrates will be discharged.

56 indicates a trough into which the tailings will be discharged.

When the table is in operation the heavier matter is thrown to the upper side a of the table and is washed by the clear water and will travel down along the upper side of the table, and while traveling down the table will lie in a band, the edges of which band will be substantially parallel with the upper wall 54 of the table. For this reason the preferred form of the table is a pentagon, the power side of the table being at right angles with the feed and discharge ends and extending from near the lower bumping-beam p to the feed end in a right line, and the lower corner of the table between the power side and discharge end may be cutaway on a line parallel or approximately so with the upper side of the table. The table has an upwardlyprojecting rim or wall 54 57 58 59 of a suitable depth to retain the pulp on all sides excepting the discharge end;

The cam connecting-rod 30, which pulls the table in one direction, and the bumping-spring connecting-rod 37, which pulls the table in the other direction, are attached to the table substantially at the lateral line of the center of gravity, so that the weight and surface of the table are approximately equally divided between the feed end and the discharge end of the table along the line to which the power is applied, thus causing the table to move sidewise without any tendency to rotatethat is to say, that the table is thus balanced to move laterally in a straight line with the least tendencytomovelongitudinally. Theaction of the parallel bars 48 and 49 is such as to correct any tendency which the table would otherwise have to move endwise.

In practical operation the cam 25 may be driven at a speed of two hundred and thirty to two hundred and sixty revolutions per minute, and this with any throw desired from the minimum to the maximum above stated. The cam 25, acting upon the cam-lever 26, compresses the spring 43, which spring imparts the motion to the table in a gradual manner to draw the table toward the power side of it IO the frame against the force of the bumpingspring 19. The tension of the tempering and cushioning spring 31 and of the tension-spring 28 assists in starting the table to swing toward the power side under the action of the spring 43. When the cam has moved the shoe 29 to the fullest extent to draw the table away from the bumping-posts, the bumpingspring 19 draws the table forcibly toward the percussion side and holds the shoe 29 against the force of the tension-spring 28 in constant contact with the cam until the instant of the bump. On this return stroke the table is first received by the cushioning-spring 31, and its motion is thereby gradually checked until the bumping-beams 0 p reach the bumping-faces 15 10, respectively, when the table is brought to a sudden stop, from which it is carried back immediately by the combined action of the recoil of the bumpers and the force of the cushioning and tempering spring and tension-spring and the operation of the cam, which immediately engages the shoe to again draw the table to the end of its throw at the power side of the table. Then the action above described is repeated. It is to be observed that at the moment of percussion the table has swung farther away from the power side than it normally stands when under the influence of the springs alone, and therefore the shoe 29 will at that instant be closer to the axis of the cam than it will normally stand when the table is at rest.

In Fig. XI the position of the shoe when the table is at rest under the adjustment shown is shown in solid lines, and theposition of the shoe when the table is bumping is indicated in dotted lines below the solid position.

The position when the table is fully thrown to the power side is indicated by the upper dotted lines. The form of the cam may be varied; but in the drawings I have shown a heart-cam of a form which I deem most desirable. In this form the cam is laid off by ninths. Dotted lines 61 62 63 64 65 66 67 68 69 indicate nine equidistant radii upon which to lay out the cam. From the shortest radius 61 the cam-surface increases in an approximately regular convolute to the sixth radius 66, from which radius it decreases in an approximately regular convolute to the first radius 61. In this form of cam the cam which revolves in the direction indicated by the arrow will pick up the shoe 29 soon after the lowest point of the surface at radius 61 has passed beneath the shoe and will throw the shoe upward as the radii increase in length from 62 to 63, and so on until the radius 66 has beenreached. Then the cam willallow the shoe to return under the action of the bumping-spring 19 until the cam escapes from the shoe between the radii 69 and 61, at which instant while the shoe is free from the cam the bump takes place. Then the cam catches the shoe while the table is under the influence of the recoil and the cushioning-spring 31 and tension-spring 28 and assists the cushioningspring and tension-spring in returning the table toward the power side, and the cam completes the stroke-that is to say, the cam overtakes the shoe immediately after the table has started back toward the power side and while it is yet being acted on by the cushioning and tempering spring.

The length of thelinks fg at the discharge end of the table is such as to avoid any perceptible rise and fall of the swinging table at that end. The yoke b, which carries the links (1 e, which support the feed end of the table, is swung freely by a flexible connection 0 to compensate for the less length of links (Z 6 and to allow a free and ample lateral movement of the table in a practically horizontal plane. The table a slopes downward longitudinally from head to tail and transversely from the percussion side. The links are loosely suspended and are loosely connected with the table, so that they willallow the table to swing horizontallywithoutverticalvibration. Any vertical vibration is objectionable, as it would cause the heavy mineral to bound up from the face of the table andpass off with the gangue. Since the heart-cam which consti 'tutes the means for maintaining the vibration 'of thetable is absolutely free from the table,

the vibration of the table can be s'o adj Listed by adjusting the tension ofthe balancing-springs that the cam and table will move in perfect consonance with each other, thus giving the delicate action which is requisite for moving the heavy mineral across the table without causing it to bound upward from the face of the table.

Having now particularlydescribed and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. In an ore-concentrator the combination of a frame; a concentrating-table which slopes longitudinally downward from head to tail and discharges over the edge at the tail; a yoke; flexible means at the middle of the yoke connected with the frame at one end thereoffor supporting the yoke; links at the ends of the yoke respectively, loosely connected with the yoke and with the opposite sides of the table at one end thereof; two table-supporting links at the other end of the frame, the same being respectively loosely connected with the frame and with the table att-he opposite sides thereof; intermittent. means for moving the table in one direction; resilient means for returning the table; and means for stopping the table at its return; said table also sloping transversely downward from the concussion side to the opposite side substantially as and for the purpose set forth. r

2. In an ore-concentrator the combination of a frame; a concentrating-table which slopes longitudinally downward from head to tail and discharges over the edge at the tail; a yoke; flexible means at the middle of the yoke adjustably connected with the frame for supporting the yoke; links at the ends of the yoke respectively, loosely connected with the yoke and with the opposite sides of the table at one end thereof; two table-supporting links at the other end of the table, the same being respectively, loosely connected with the frame and the table at opposite sides thereof; intermittent'means for inoving'the table in one direction; resilient means for returning the table; means for stopping the table atits return; and resilient means for starting the table in the direction in which it is moved by said intermittent means; said table also sloping transversely downward from the concussion side to the opposite side substantially as and for the purpose set forth.

3. The combination of a concentrating-table which slopes downward from head to tail and discharges over the edge at the tail; links loosely suspended and loosely connected with the table, and suspending such table; means for intermittently moving the table in one direction; a spiral spring arranged to exert a direct pull on the table for returning the table; and resilient means to normally hold the table at restintermediate the ends of its th row;

' said table also sloping downward from the side to which it is returned by said spring substantially as and for the purpose set forth.

' 4. In an ore-concentrator the combination of a table; links supporting the table; parallel bars pivoted to the table at the discharge end thereof and extending toward the feed end of the table and there secured to a support; means for operating the table laterally; and means atone side of the table for arresting the movement of the table.

5. In an ore-concentrator the combination of a table; links supporting the table; means for intermittently moving the table in one direction; a spring for returning the table; means for arresting the return movement of the table; and table-guiding bars connected with the table at the discharge end thereof and extending toward the feed end and fastened to a support.

6. The combination of a concentratingtable which slopes downward from head to tail and discharges over the edge at the tail; links loosely suspended and loosely connected with such table, and suspending said table; means for intermittently moving the table in one di-' reotion; a spring for returning the table in the other direction; means for adjusting the tension of said spring; stationary means for stopping the table on itsreturn; and a tempering-spring to yieldingly check the motion of the table immediately before the table strikes the stationary stop; said table also sloping downward from the concussion side to the opposite side substantially as and for the purpose set forth.

7. The combination of a concentrating-table; links suspending said table; means for intermittently moving the table in one direction; a spring for returning the table; stathe motion of the table immediately before the table strikes the stationary stop; and additional resilient means to normally hold the table at rest intermediate the ends of its path.

8. In an ore'concentrator, the combination of a concentrating-table which slopes downward from head to tail and discharges over the edge at the tail; loosely-suspended links loosely connected with the table to allow the same to swing in a horizontal plane; intermittent means for moving the table in one direction; a spring for returning the table; means for-adjusting the tension ofsaid spring; means for arresting the movement of the table at its return; and resilient means to normally hold the table intermediate the ends of its path; said table also sloping downward from the concussion side to the opposite side substantially as and for the purpose set forth.

9. Thecombination withloosely-suspended links; of an ore-concentrating table loosely connected with said links and sloping downward from the head to the tail and discharging over the edge at the tail; resilient means for balancing the table intermediate the ends of its path; means for adjusting the tension of said resilient means; and means disconnected from the table for moving the table .to and fro in such path in consonance with the spring-controlled vibration of the table; said table also sloping from one side to the other substantially as and for the purpose set forth.

10. The combination withan ore-concentrating table which slopes from head to tail and discharges over the edge at the tail; of

springs for balancing the table intermediate the ends of its path; means for adjusting the tension of the springs; and means disconnected from the table for vibrating the table in consonance with the spring-controlled movement thereof; said table also sloping from one edge to the other substantially as and for the purpose set forth.

11. In an ore-concentrator, the combination with a swinging table sloping from head to tail and discharging over the edge at the tail; of means for operating the table laterally; adj ustable resilient means for timing the vibrations of the table; and stays for staying the table against endwise motion; said table also sloping downward from one edge to the other substantially as and for the purpose set forth.

12. In an ore-concentrator the combination with a swinging table; of means for operating the table laterally; and two parallel rods connected with the table on opposite sides of the mid-line thereof at the discharge end, and extending thence toward the feed end and fastened to a support.

13. In an ore-concentrator the combination of a concentrating-table means for suspending said table; a lever; a rod connecting one arm of the lever. with the table; a cam to operate the lever to swing the table to one side; a tension-spring connected with the lever and tending to hold the same away from the cam; a spring connected with the table to swing the table in the direction opposite to thatin which it is moved by the operation of the cam; and means for arresting the motion of the table when the same is thrown by the spring.

14. In an ore-concentrator the combination of a concentratingtable; means for suspending said table to allow it to swing sidewise; a lever; a rod connecting one arm of the lever with the table; a lever-operating cam to engage the other end of the lever; a spring tending to hold said other end of the lever away from the cam; a spring for moving the table in the direction opposite to that in which it is moved by the action of the cam; a stationary stop for stopping the table when it is thrown by the spring; and a spring to yieldingly check the motion of the table immediately before the table strikes the stationary stop.

15. In an ore-concentrator the combination of a concentrating-table; means for suspending said table; table-operating means connected with the table; a cam for actuating said table-operating means to move the table in one direction; a spring tending to hold said table-operating means away from the cam; and a spring for moving the table in the direction opposite to that in which it is moved by the action of the cam.

' 16. In an ore-concentrator the combination of a concentratingtable; means for suspen ing said table; tableoperating means connected with the table; a cam for actuating said table-operating means to move the table in one direction; a spring tending to hold said table-operating means outof engagement with the cam during a portion of the rotation of the cam; a spring for moving the table in the direction opposite to that in which it is moved by the action of the can]; means for stopping the table at the end of its vibration away from the can]; and a tempering-spring to yieldingly check the motion of the table immediately before the table comes into contact with the stop.

17. In an ore-concentrator the combination of a concentrating-table; means for suspending said table to allow the same to swing; stays connected with the table at its discharge end and extending toward the feed end of the lable to prevent longitudinal movement of the table; means for moving the table in one direction laterally; a cam for operating said means;

a spring for normally holding said means free from the cam during a portion of the rotation of the cam; a spring to move the table in a direction opposite that in which it is moved by the cam; and means for arresting the movement of the table at the end of its vibration away from the cam.

18. In an ore-concentrator the combination of a yoke; means for pivotally supporting the yoke at its middle; means for vertically adjusting said support; links at the opposite ends of the yoke, respectively connecting the yoke with the opposite sides of the table at the feed end thereof; screw-supported links connected with the discharge end. of the table on opposite sides thereof, respectively; nuts for adjusting said screws vertically; tableopcrating means for moving the table in one direction; a cam for operating said tabl.eopcrating means; springs tending to hold said table-operating means away from the cam; two stay-bars connected with the table at the discharge end. thereof on opposite sides of the mid-line of said table and extending thence toward the feed end of the table and fastened to stationary supports; a spring for moving the table in a direction opposite to that in which it is moved by the operation of the cam; a stationary stop for stopping the table at the end of its vibration away from the cam and a tempering-spring to yieldingly check the motion of the table immediately before the table strikes the stationary stop.

' 19. In an oreconcentrator the combination of a concentrating-table; a yoke; means for pivotally supporting the yoke at its middle; means for vertically adjusting said support; links at the opposite ends of the yoke conmeeting the yoke with the opposite sides of the table at the feed end thereof; screw-supported links connected with the discharge end of the table at opposite sides thereof; means for adjusting said screws vertically; tableoperating means for moving the table in. one direction; a cam for operating said table-operating means; a spring tending to hold said table-operating means away from the cam; two stay-bars connected with the table at the discharge end thereof on opposite sides of the mid-line of said table and extending thence toward the feed end of the table andfastened to stationary supports; a" spring for throwing the table in a direction opposite to that in which it is moved by the operation of the cam; a stationary stop for stopping the table at the endof its vibration away from the cam; and a tempering-spring toyieldingly check the motion of the table immediately before the table strikes the stop.

20. The combination of a concentratingtable; means forsuspendingsaid table to allow it to swing; a bell-crank lever; a connecting rod connecting one end of said lever with the table; a cam arranged to intermittently engage the other end of the lever to actuate the same; a spring tending to hold said other end of the lever away from the cam; and a spring for moving the table in a direction opposite to that in which it is moved by the cam.

21. The combination of a concentratingtable; means for suspending said table to allow it to swing; a bell-crank lever; an adadjustable connecting-rod connecting one end of said lever withthe table; a cam ar ranged to intermittently engage the other end of the lever to actuate the same; a spring tending to hold said other end of the lever away from the cam during a portion of the rotation of the cam; and a spring for moving the table in a direction opposite to thatin which it is moved by the cam.

22. In a concentrator the combination with 7 aswingingtable; of abell-crank lever; a cam In testimony whereof I have signed my in to intermittently engage one arm of said lename to this specification, in the presence of ver to actuate the same; a pin journaled in two subscribing Witnesses, at Los Angeles, the other arm of the lever; a connecting-rod California, this 2d day of August, 1900. connected With the table and passing through 7 said pin; means for adjustably fastening the LUTHER Look rod in said pin; and yielding means tending Witnesses:

to hold the free end of the bell-crank arm JAMES R. TOWNSEND,

away from the cam. JULIA TOWNSEND. 

